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#define dbg if(0)
#include <iostream>

using namespace std;
typedef unsigned long long ull;
const int BOARD_SIZE = 3300*3300;
const ull MOD = 1000000007;
char board[BOARD_SIZE];

void print_board(int n){
  for(int i = 0; i < n; ++i){
    for(int j = 0; j < n; ++j){
      cout << (board[i*n+j]==0 ? '.' : '#');
    }
    cout << endl;
  }
}

int check_position(int i, int n){
  if(board[i] == 1){
    return 0;
  }
  int x = i%n;
  int y = i/n;
  dbg cout << "i: " << i << " checking x: " << x << " y: " << y << endl;
  bool has_neighbour = false;

  if(x > 0 && board[y*n + x - 1] == 1){
    has_neighbour = true;
  }
  if(x < n-1 && board[y*n + x + 1] == 1){
    dbg cout << "has_neighbour" << endl;
    has_neighbour = true;
  }
  if(y > 0 && board[(y-1)*n + x] == 1){
    has_neighbour = true;
  }
  if(y < n-1 && board[(y+1)*n + x] == 1){
    has_neighbour =  true;
  }
  if(has_neighbour){
    board[i] = 1;
    return 1;
  }
  return 0;
}

void brut1(int n){
  ull counter = 0;
  for(int i = 0; i < n*n; ++i){
    int can_put_i = check_position(i, n);
    counter += can_put_i;
    if(can_put_i)
      board[i] = 0;
  }
  cout << counter%MOD << endl;
}

void brut2(int n){
  ull counter = 0;
  for(int i = 0; i < (n*n)-1; ++i){
    for(int j = i+1; j < n*n; ++j){
      dbg cout << "i: " << i << " j: " << j << endl;
      int can_put_i = check_position(i, n);
      int can_put_j = check_position(j,n);
      if( can_put_i && can_put_j){
        dbg cout << "Adding" << endl;
        ++counter;
      }
      if(can_put_i)
        board[i] = 0;
      if(can_put_j)
        board[j] = 0;
    }
  }
  cout << counter%MOD << endl;
}

void brut3(int n){
  ull counter = 0;
  for(int i = 0; i < (n*n)-2; ++i){
    for(int j = i+1; j < (n*n)-1; ++j){
      for(int k = j+1; k < n*n; ++k){
        int can_put_i = check_position(i, n);
        int can_put_j = check_position(j,n);
        int can_put_k = check_position(k, n);
        if(can_put_i && can_put_j && can_put_k)
          ++counter;
        if(can_put_i)
          board[i] = 0;
        if(can_put_j)
          board[j] = 0;
        if(can_put_k)
          board[k] = 0;
      }
    }
  }
  cout << counter%MOD << endl;
}


void brut4(int n){
  ull counter = 0;
  for(int i = 0; i < (n*n)-3; ++i){
    for(int j = i+1; j < (n*n)-2; ++j){
      for(int k = j+1; k < (n*n)-1; ++k){
        for(int l = k+1; l < n*n; ++l){
          int can_put_i = check_position(i, n);
          int can_put_j = check_position(j,n);
          int can_put_k = check_position(k, n);
          int can_put_l = check_position(l, n);
          if(can_put_i && can_put_j && can_put_k && can_put_l)
            ++counter;
          if(can_put_i)
            board[i] = 0;
          if(can_put_j)
            board[j] = 0;
          if(can_put_k)
            board[k] = 0;
          if(can_put_l)
            board[l] = 0;
        }
      }
    }
  }
  cout << counter%MOD << endl;
}


int main(){
  int n, k;
  char tmp;
  cin >> n >> k;

  for(int i = 0; i < n; ++i){
    for(int j = 0; j < n; ++j){
      cin >> tmp;
      board[i*n + j] = tmp == '.' ? 0 : 1;
    }
  }

  dbg print_board(n);

  if(k == 1)
    brut1(n);
  if(k==2)
    brut2(n);
  if(k==3)
    brut3(n);
  if(k==4)
    brut4(n);

  return 0;
}